Man robs gas station while wearing underwear. On his head.

Red and Blue Lightbar of a Police Car (shiyali/Getty Images/iStockphoto)

UPPER CHICHESTER, Penn. — A man armed with a knife and disguising his face with a pair of underwear robbed a suburban Philadelphia gas station Thursday.

The suspect entered Upper Chichester Shell Gass Market shortly before 11 p.m., pulled out a knife and demanded the cash from the register, police said.

The employee handed over between $100-$200 and the suspect fled.

According to the victim, the robber was about 5 foot 8 inches tall with a thin build. He was wearing all dark clothing, including a hat and gloves, but also had his face covered with a pair of underwear, police said.

Surveillance video showed the suspect arriving on foot from around the side of the building. He was only in the store for about 20 seconds before he fled with the cash, authorities said.

Police responded, and followed the footprints in the snow across the parking lot to the Redzone bar. The tracks continued through the adjacent field and toward the rear of some nearby homes.

K-9 Officer Mike Jones and his partner followed the suspect's path to a dump truck that was parked in the open field. At the rear of the truck, the dog found several items of clothing. The K-9 team tracked another 100 feet and located a pair of black gloves.

“We recovered gloves, a hat and the underwear,” said Detective Sgt. Thomas McNichol.